Remove some tests of internal API

[MichaelChirico]

Closes #1692.

[codecov]

Codecov Report

Attention: Patch coverage is 60.00000% with 2 lines in your changes missing coverage. Please review.

Project coverage is 99.25%. Comparing base (0a47a3f) to head (cb67e96).

Files with missing lines	Patch %	Lines
R/make_linter_from_regex.R	0.00%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2801      +/-   ##
==========================================
- Coverage   99.64%   99.25%   -0.39%     
==========================================
  Files         127      127              
  Lines        6989     6969      -20     
==========================================
- Hits         6964     6917      -47     
- Misses         25       52      +27     

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[MichaelChirico]

Wait for #2802